This invention relates generally to machinery for assembling plastic carriers onto containers to form conveniently handled multipacks.
Plastic carriers, such as are disclosed in U.S. Pat. Nos. 4,462,494 and 4,219,117 in the form of an apertured plastic sheet or strip, are well-known in the art and provide a convenient, inexpensive way to retain individual containers in multipacks. Such carriers are particularly useful in the brewing and soft-drink canning industries and are used to retain cans so as to form the six, eight and twelve packs familiar to purchasers of such goods. Although such packages can be assembled by hand when relatively few cans are involved, hand assembly is impractical in commercial brewing or canning operations wherein thousands of cans are processed per hour. Thus, various machines have been proposed for automatically assembling plastic carriers onto containers with speed, reliability and economy.
One known form of carrier assembling machine is shown, or example, in U.S. Pat. No. 3,032,944 to Hull et al., and is typified by a rotating drum around which a number of carrier aperture expanding jaws are mounted. The jaws are axially slideable along a plurality of guide rods, and a pair of cams adjacent opposite ends of the drum function to drive the jaws toward and away from each other as the drum rotates, thereby expanding the carrier for assembly onto the cans. Although effective, such machines are complex, expensive and, because of their many sliding elements, prone to wear and increased maintenance costs.
Another known form of carrier assembling machine is shown, for example, in U S. Pat. No. 4,250,682 to Braun and is also typified by a rotating drum having thereon mounted a number of carrier aperture expanding jaws. However, and in contrast to the earlier-described machine, only half of the expanding jaws are axially slideable in response to rotation of the drum, the remaining jaws being axially fixed. Although this construction reduces, by one-half, the number of sliding elements, a number of sliding elements nevertheless remain. Though an improvement, such a machine is, nevertheless, still prone to wear and increased maintenance costs.
An alternative approach to assembling Plastic carriers to containers is shown in the inventor's U.S. Pat. No. 3,383,828. In this approach, a plurality of pin elements are adapted to engage the carrier and are driven so as to transcribe arcuate paths and thereby expand the carrier for assembly onto the containers. Although effective, this mechanism, too, is complex, prone to wear, and can lead to increased maintenance costs.
In view of the foregoing, it is a general object of the present invention to provide a new and improved apparatus for assembling carriers onto containers.
It is a more specific object of the present invention to provide a new and improved carrier assembling machine capable of economical manufacture and operation.
It is a still more specific object of the present invention to provide a new and improved carrier assembling machine wherein sliding movement of carrier aperture expanding elements is eliminated.